1. Field of the Invention
This disclosure pertains to a radiant panel which may be used for both heating and cooling purposes. More specifically, this disclosure shows an extruded panel having a copper tube attached to the back surface thereof wherein a plurality of panels are held in place adjacent one another by a cross member.
2. Description of the Prior Art
The prior art radiant panel arrangements includes three types of constructions. First, the so-called tube-on-sheet configuration, provides an aluminum sheet with a copper tube soldered thereto as shown in the Beck U.S. Pat. No. 3,698,475 which describes the method of producing such a simple product. The second type of construction provides an aluminum sheet with 90.degree. curl flange and a galvanized pipe mechanically attached to the curl flanges of the sheet and held in place by clips or other such similar mechanical devices and as described in the Baran U.S. Pat. No. 2,818,235. There is no solder or other type of metallurgical bonding between the galvanized pipe and the sheet, although at times mechanical arrangements have utilized adhesives to provide a bond between pipe or tube and aluminum sheet and to improve heat transfer characteristics between the two members.
The third type of arrangement is exemplified by the Beck U.S. Pat. No. 4,080,703 which shows an extruded aluminum panel having upstanding saddles on the back surface. The upstanding saddles receive copper tubes which are subsequently deformed at an elevated temperature to hold the tube in the saddle. Afterwards, the tube may be hydraulically expanded to the saddle contour by using a pressurized holding die on the top of the tube.
These three types of constructions have met with limited acceptance; however, because of certain problems with each of the prior art products, the search has continued for a more economical and efficient arrangement. More specifically, the so-called tube-on-sheet arrangement provides certain quality control problems to ensure that the panel is not distorted or inflicted with aesthetically undesirable surface irregularities when it is heated to the solder melting point when joining the copper tube to the aluminum sheet. The second type of arrangement, a mechanically-held tube arrangement, has met with other types of objections, but not cosmetic objections due to poor appearance. The mechanically-held galvanized pipe and aluminum sheet have not been widely accepted because the heat transfer characteristics are not sufficient enough to allow the panel to be used for both heating and cooling. The heat transfer characteristics result in a low efficiency and insufficient output. The third type of arrangement, the extruded sheet with the deformed copper tube, has also met with some objections because of the expense involved and the inability to prove the surface contact between the tube and sheet. Deforming the copper tube into the oval saddle gives rise to the question of the surface contact which cannot be proved by visible inspection. Also, the deformation of the sheet and tube occurs at an elevated temperature, above the operating temperature of the panel, thus requiring heated dies and special equipment for handling the hot panels. This type of design requires specialized equipment and results in a very expensive product.
The problems described above are overcome by the present method and produce arrangement which provides the heat transfer characteristics of the soldered tube-on-sheet panels without the distortion problems and without the high expense involved with the extruded-deformed tube arrangement.